Doré Copper Announces its Preparation Plans to Dewater the Former Joe Mann Gold Mine and Cedar Bay Copper-Gold Mine

TORONTO, March 05, 2021 - Dor? Copper Mining Corp. (the "Corporation" or "Dor? Copper") (TSXV: DCMC; OTCQB: DRCMF; FRA: DCM) is pleased to announce its preparation plans for the dewatering of the former Joe Mann and Cedar Bay mines which closed in 2007 and 1990, respectively.

The Company recently conducted water sampling tests down each shaft which returned positive results:

Cedar Bay Mine Sampling (November 2020):
The Cedar Bay mine ceased operations in 1990 after having produced 3.9 million tonnes (Mt) of ore grading 1.63% Cu and 3.21 g/t Au.

Water was sampled down the shaft every 100 meters down to the deepest development level of 760 meters for a total of seven samples. Video inspection of the shaft indicated no deformation with rails intact and in place. The average pH was 6.52, mildly acidic or near neutral (pure water has a pH of 7.0). Heavy metals were low in concentration with many metals below detection limits. The characterization demonstrated the presence of dissolved solids that will also need to be considered in the selection of the water treatment system for dewatering.

Joe Mann Mine Sampling (February 2021):
The Joe Mann mine ceased operation in 2007 after having produced 1.2 million ounces of gold (4.75 Mt of ore grading 8.26 g/t Au and 0.25% Cu).

Water was sampled down the shaft every 100 meters down to the deepest development level of 1,150 meters for a total of 12 samples. Video inspection indicated that the shaft is in excellent condition. The average pH was 7.35, indicating a slightly basic water chemistry. Heavy metals were low in concentration with many metals below detection limits. Copper and zinc concentrations were below detection limits in the majority of the samples. The characterization also demonstrated the presence of dissolved solids in this shaft, which will have to be considered in the choice of the water treatment system.

Ernest Mast, President and CEO, stated: "We are greatly encouraged by the good condition of the shafts and benign water characteristics in both mines. Following completion of the dewatering assessment, we will be in a position to make a decision on the dewatering of these mines. The dewatering would provide Dor? Copper underground access to the lowest levels of the mines and accelerate our exploration and development timeline while lowering our drilling costs and improving drilling accuracy."

Following the positive results of the water samples, Dor? Copper will commence the design of the dewatering programs. This assessment will include the costs and timelines of the dewatering, water treatment process, final treated water destination and precipitate disposal for each mine. The work is expected to be completed by year-end.

Concurrently with the assessment, the Corporation will be submitting in April an application for attestation of exemption (demande d'attestation de non-assujettissement) to the Qu?bec Ministry of Environment and Fight Against Climate Change. Subject to this approval, the Company would proceed to the second step, which is the application to the regional MELCC under Article 22. It is expected that approval would be received within six to eight months.

The Corporation contracted BluMetric Environmental Inc. out of Montreal to sample and analyze the water from both shafts.

Ernest Mast, Eng., President and CEO of the Company and a "Qualified Person" within the meaning of National Instrument 43-101, has reviewed and approved the technical information contained in this news release.

New Appointment

Dor? Copper has appointed Emilie Belanger as Manager Environment and Permitting. Ms. Belanger is an environment and sustainability professional with 20 years of experience in the mining industry. She founded Envirosynergie Services in 2014, which was subsequently acquired by GCM Consultants, where she remained until recently as Director of Environmental Services. Prior, she worked at Quebec Lithium as Environmental Superintendent and at Genivar as Assistant Director of the ATNQ (Abitibi-T?miscamingue et le Nord-du-Qu?bec) Environmental Department. Ms. Belanger is very familiar with the "brownfield" assets of Dore Copper having worked for four years in the Environmental Department at Campbell Resources' operations in the Chibougamau area.

About Dor? Copper Mining Corp.

Dor? Copper Mining Corp. is a copper-gold explorer and developer in the Chibougamau area of Qu?bec, Canada. Dor? Copper has consolidated a large land package in the prolific Lac Dor?/Chibougamau mining camp that has historically produced 1.6 B lbs of copper and 3.2 M oz of gold. In addition, the Corporation has optioned the high-grade Joe Mann gold mine (historical production 1.17 M oz at 8.26 g/t Au). The land package includes 12 former producing mines, deposits and resource target areas within a 60-kilometer radius of the Corporation's 2,700 tpd mill (Copper Rand Mill).

The Corporation's current focus is to grow mineral resources and re-develop the high-grade Corner Bay (Cu-Au), Cedar Bay (Au-Cu), and Joe Mann (Au) deposits. The Corporation has resumed its drilling program starting at Corner Bay, which will lead to an updated mineral resource estimate in Q2 2021 and a PEA in H2 2021.
For further information, please visit the Corporation's website at www.dorecopper.com or refer to Dor? Copper's SEDAR filings at www.sedar.com or contact:

Cautionary Note Regarding Forward-Looking Statements
This news release includes certain "forward-looking statements" under applicable Canadian securities legislation. Forward-looking statements include predictions, projections and forecasts and are often, but not always, identified by the use of words such as "seek", "anticipate", "believe", "plan", "estimate", "forecast", "expect", "potential", "project", "target", "schedule", "budget" and "intend" and statements that an event or result "may", "will", "should", "could" or "might" occur or be achieved and other similar expressions and includes the negatives thereof. All statements other than statements of historical fact included in this release, including, without limitation, statements regarding the timing and ability of the Corporation to receive necessary regulatory approvals, and the plans, operations and prospects of the Corporation and its properties are forward-looking statements. Forward-looking statements are necessarily based upon a number of estimates and assumptions that, while considered reasonable, are subject to known and unknown risks, uncertainties and other factors which may cause actual results and future events to differ materially from those expressed or implied by such forward-looking statements. Such factors include, but are not limited to, actual exploration results, changes in project parameters as plans continue to be refined, future metal prices, availability of capital and financing on acceptable terms, general economic, market or business conditions, uninsured risks, regulatory changes, delays or inability to receive required regulatory approvals, health emergencies, pandemics and other exploration or other risks detailed herein and from time to time in the filings made by the Corporation with securities regulators. Although the Corporation has attempted to identify important factors that could cause actual actions, events or results to differ from those described in forward-looking statements, there may be other factors that cause such actions, events or results to differ materially from those anticipated. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. The Corporation disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

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